The present invention relates in general to an endoscopic system, and it more particularly relates to an endoscopic system which is adapted to facilitate greatly the viewing of cavities in the body.
Different types and kinds of endoscopes have been used in the examination of cavities including the inner eye, the bladder, the inner ear, and the like. While the endoscopes have been satisfactory for some applications, they all suffer from various different problems all relating to the ability to facilitating the viewing of the inner surfaces of body cavities in a convenient manner. For example, in order to examine the inner eye, an ophthalmoscope is used to view the hollow spherical interior of the inner eye. Such examination is referred to as a fundus or eyegrounds examination and includes the examination of the optic disc, retina, retinal vessels, macula and the choroid. In order to perform such an examination, mydriatic solutions are used to dilate the pupil to facilitate the examination. There are basically two types of ophthalmoscopes in use today--the indirect and the direct ophthalmoscopes. The direct ophthalmoscope is a hand-held instrument which includes a strong light that can be directed into the eye under examination. The light reflected back from the fundus of the eye extends back through a small aperture in the ophthalmoscope to the examiner's eye. The aperture of the instrument is held in close proximity to the eye of the examiner as well as the eye under examination. A series of lenses usually mounted in a radially-spaced apart manner on a disc are used to focus the reflected light back to the eye of the examiner. Although such an instrument has been found to be highly successful, it enables the examiner to view the greater portion only of the retina up to the equator but not beyond the equator. It is highly desirable to view the entire retina up to the ora serrata so that ocular pathology can be detected and so that the instrument can be used conveniently during surgery. Therefore, the indirect opthalmoscope was developed and includes a convex lens which is held between the ophthalmoscope and the patient's eye under examination. The opthalmoscope includes lenses to accommodate the eye of the observer and is held several centimeters from the eye under examination. The use of the lens enables the examiner to view substantially the entire eyegrounds up to and including the ora serrata. However, the indirect ophthalmoscope provides lower magnification and produces an inverted image. It is also cumbersome to use since the ophthalmoscope, including the light source, is mounted on the head of the examiner and the lens is held in the hand. Such a device is somewhat difficult to use and requires a great deal of experience before an examining physician acquires the skill necessary to properly use it. Additionally, in both the direct and indirect ophthalmoscope, the examining physician must employ skillful hand-eye coordination to scan the eyegrounds during the examination. At all times, the examining physician must retain the fundus disc in view for orientation purposes, otherwise the physician is unable to know what portion of the eyegrounds is being visualized. Thus, the physician must acquire the necessary skill through repeated use. Additionally, during eye surgery, the use of the hand-held ophthalmoscopes requires difficult manipulations to employ the surgical instruments necessary to perform the surgical procedure as well as viewing the eyegrounds to observe the area in question. Ordinarily, the physician performing surgery on an eye views the eyegrounds through the ophthalmoscope and then uses the surgical instrument without visualizing the eyegrounds. After performing the surgical procedure, the physician sets aside the surgical instrument and then views the surgical area by means of the ophthalmoscope, and thus such a procedure is awkward and time consuming. Therefore, it would be desirable to view the eyegrounds without the necessity of holding a part or all of the ophthalmoscope in the hand so that the hands can be freed to use the surgical instruments. Also, in a teaching institution, for example, a student must attempt to view the eyegrounds for educational purposes and the teacher is unable to know exactly what the student is seeing through the ophthalmoscope, and, therefore, it would be desirable to establish an image of the cavity of the eye or other cavity of the body for several persons to view.
Therefore, while the ophthalmoscope currently being used has been satisfactory for some applications, it would be highly desirable to have a new and improved endoscopic system, which can view large areas of a cavity of the body. For example, it would be desirable to have an improved ophthalmoscopic system which can view substantially all of the retina up to the ora serrata. Such an opthalmoscopic system should be convenient to use and not require a great deal of hand-eye coordination so as to greatly eliminate or reduce the amount of time necessary in learning how to use the ophthalmoscopic system in a proper manner. Such an ophthalmoscopic system should provide the examining physician with an image of the retina without requiring the physician to hold in his hands any part of the ophthalmoscopic system so as to free his hands for other activities, such as using surgical instruments during a surgical procedure. Such a new and improved ophthalmoscopic system should also enable the physician to quickly view an image of the eyegrounds under examination and then record that image photographically for record purposes, since it is oftentimes desirable to observe any subtle changes occurring in the eyegrounds over a period of time, whereby a physician using the improved ophthalmoscopic system could examine a patient's eyes periodically and record pictures of the eyegrounds for comparison purposes to alert the physician as to any pathological changes occurring so that early treatment can be accomplished.
Therefore, in general, the principal object of the present invention is to provide a new and improved endoscopic system, which enables an examining physician to clearly visualize large areas of the interior of cavities within the body in a convenient manner with little or no need for hand-eye coordination, and which can be used to create an image of the interior of the cavity that can be conveniently photographed for record purposes.
Another object of the present invention is to provide such a new and improved endoscopic system, which can create an image of large areas of the interior of the cavity so that a single photograph can be taken of them for record purposes, and which can facilitate surgical procedures by eliminating the need for the physician to hold parts of the viewing instrument in the hand while performing the surgical procedure.
Briefly, the above and further objects of the present invention are realized by providing an endoscopic system, which includes a light source for directing at least one light beam toward the interior of the cavity under examination to illuminate it and a plurality of lenses for focusing the light reflected back outwardly away therefrom along a plurality of spaced-apart paths in adjacent fields of view. A plurality of spaced-apart camera devices receives the reflected light from the illuminated cavity via corresponding ones of the plurality of paths and reproduce the adjacent fields of view. According to the preferred form of the present invention, the camera devices include closed-circuit color television cameras which are connected electrically to a plurality of color television receivers having their video display screens positioned adjacent to one another to provide a composite image of the cavity under examination. Such image can be readily photographed by, for example, an instant still camera which can provide a photograph of the composite image in a short time for record purposes. Also, the television cameras can also be connected into a closed-circuit television system of a teaching institution or a hospital so that the composite image of the cavity can be viewed remotely for education purposes. Also, the composite image can be transmitted over telephone lines or the like to remote locations for diagnosis by specialists.